1. Field of the Invention
The present invention relates to a forming method of an ink jet print head substrate and an ink jet print head substrate, and a manufacturing method of an ink jet print head and an ink jet print head.
2. Related Background Art
Conventionally an ink jet recording method is known, as indicated by Japanese Patent Application Laid-Open No. 54-51837, in which recording is performed by applying thermal energy to liquid to generate a force to discharge a liquid droplet. Specifically, in this ink jet recording method, a liquid under thermal energy application is overheated to generate bubbles, the force due to the bubble generation produces a liquid droplet through an orifice at a tip of a recording head section, and then this droplet adheres to a recording medium, thereby achieving information recording.
An ink jet print head used in this recording method generally comprises: an orifice prepared in order to discharge liquid; a liquid discharging section with a liquid flow path comprising a heating section in communication with the orifice, thermal energy for discharging a liquid droplet being applied to the liquid in the heating section; a heat-generating resistive layer as a thermal converter that is means to generate thermal energy; an upper protective layer for protecting the heat-generating resistive layer from ink; and a lower layer for reserving heat.
Methods of forming nozzles and discharge ports with high density and high precision for such an ink jet print head are proposed, for example, in Japanese Patent Application Laid-Open No. 5-330066, and Japanese Patent Application Laid-Open No. 6-286149 is proposed.
In recent years, as ink jet printers with higher level performance are present, a print head that enables higher speed printing is required. For this reason, it is proposed to increase the width for one printing in order to increase printing speed.
However, in the above-mentioned conventional example indicated in Japanese Patent Application Laid-Open No. 6-286149, in order to attain the above described object, ink discharge ports need to be arranged over a longer distance. And for this reason, it is important that adhesion between a substrate with an ink discharging pressure generating element formed thereon, and an ink flow path forming member is higher.
Therefore, for example, in Japanese Patent Application Laid-Open No. 11-348290, a method is proposed to use an adhering (closely contacting) layer comprising a polyether amide resin so as to increase the adhesion between a substrate with an ink discharging pressure generating element formed thereon and an ink flow path forming member. However, there is still a possibility of problems such as floating-up and peeling of the ink flow path forming member because of the increased nozzle row length, even if an adhering layer comprising such a polyether amide resin is used.